Olson said he sees no conflict between his conservative beliefs in democracy and his efforts now to have the courts overturn a referendum approved by voters.

"Whenever minority rights are put to a popular vote, the minority loses," he said. California's situation is especially complex, because 18,000 same-sex couples married during the period when the state supreme court allowed it and voters amended the state constitution to forbid it.

Olson, who has argued 56 cases before the Supreme Court, said it is "inevitable" that the court will decide the issue, and told the law students that the case he and Boies are preparing represents the best chance to win.